Device and method for observing or controlling a non-linear system

A device for observing a non-linear system, comprising:

• at least one sensor for supplying a measurement vector each component of which is a measurable output parameter of the non-linear system;
• a state observer processor that, based on a predetermined state representation of the non-linear system, is configured to supply an estimation of a state vector of the non-linear system according to the measurement vector supplied and a control vector of the non-linear system;
• wherein, the predetermined state representation comprises a model of non-linearity of the system in a form of a gain parameter, and one component of the state vector is the gain parameter.

A method for observing a non-linear system comprising:

• reception, by a state observer processor based on a predetermined state representation of the non-linear system, of a measurement vector each component of which is a measurable output parameter of the non-linear system;
• estimation, by the state observer processor, of a state vector of the non-linear system according to the measurement vector supplied and a control vector of the non-linear system;
• wherein the predetermined state representation comprises a non-linearity model of the system in a form of a gain parameter, and the estimation of the state vector comprises an estimation of the gain parameter as a component of the state vector.